- Museum number
STAINLESS STEEL CASED SUBSIDIARY SECONDS CLUB-TOOTH LEVER WRIST-WATCH WITH ALTIMETER AND BAROMETER AND STAINLESS STEEL BRACELET WITH BLACK FINISH.
Seventeen-jewelled lever escapement with incabloc shock-proof system; aneroid barometer box between movement and case back.
Silvered-metal dial with outer circle calibrated in mm of mercury for barometric pressure; outer, manually-set ring calibrated 0-100 is used to indicate altitude; raised baton hour markers; subsidiary seconds.
Hour and minute hands with luminous-painted stripe; red-painted central barometer hand.
Stainless-steel case with screw-on back.
Black-painted stainless-steel bracelet.
- Production date
Diameter: 40 millimetres
Thickness: 15 millimetres
- Curator's comments
- Comment from Richard Good, Catalogue of Watches in the British Museum. Vol. V (Unpublished manuscript)
Geneva, Switzerland, c. 1965
Wrist watch with altimeter and barometer and with a club tooth lever escapement.
Signature: On the dial 'FAVRE LEUBA GENÈVE bivouac SWISS MADE'
Case: A two part stainless steel case with on the case back 'BIVOUAC ALTIMETER BAROMETER 52313 and 1548'. A setable altimeter ring in black with white numerals from 0 - 100 every four and with divisions at each unit.(1)
With the watch is a black stainless steel bracelet marked '100% STAINLESS STEEL HONG KONG'
Dial & Hands: A silvered dial with rhodium plated hour batons and hands. There are luminous dots at the hours. Around the outside of the dial are the barometer markings in mm. of mercury, numbered 750 to 770 every 10 with marks at every five and with a red triangle between the two numbers in the 12 o'clock position. The hour and minute baton hands are skeletonised and filled luminous, the barometer hand is like a centre seconds hand in red.
Ebauche Marks: P 320 (Peseux).(2)
Frame: The basic movement is of straightforward layout with a bridge for the barrel another for the train and cocks for the pallets and balance. Sitting on top of the movement is the barometer movement with its own top and bottom plates held together by one screw. Three other screws pass through this assembly into the front plate using existing screw holes in this plate.
Barrel and Mainspring: A recessed cover to the barrel.
Barrel: I diameter 9.6 mm., height 1.2 mm.
Mainspring: height 1.2 mm., thickness 0.12 mm.
Barrel Arbor: diameter 3.2 mm., snailed.
Hooking: milled from the barrel wall.
Train: All the brass wheels are gilded, the centre, third and fourth wheels with five crossings. The steel escape wheel with four.
Jewelling: Jewelled bearings from the centre wheel onwards, all the jewels pressed in. Incabloc shock protection to the balance.
Escapement: A straight line layout club tooth lever escapement with short lever, double roller and D-shaped impulse pin. The exposed pallet stones have flat acting faces. A steel escape wheel with four crossings.
A mixed escapement.
No. of teeth embraced 3½.
Balance & Spring: a monometallic balance with screws. Balance diameter 9.95 mm, thickness 0.6 mm. A 'self compensating' flat spiral spring with 11 turns.
Means of Regulation: An index on the balance cock registers against a divided scale with + and -.
Train Counts and Beat Rate:
Great wheel 72 (barrel)
Centre wheel 64 pinion 10
Third wheel 60 pinion 8
Fourth wheel 70 pinion 8
Escape wheel 15 pinion 7
Beat rate 18,000
Motion work: cannon pinion 10
minute wheel 36, minute pinion 9
hour wheel 30
Barometric device: The centre pinion, which is biassed by a hairspring, is driven by a wheel with a cut-out into which a lever fits. This lever is operated on by a second magnifying lever which is in contact with the centre of the aneroid drum.
Winding System: Conventional positive stem set keyless work.
Dimensions: Case diameter 40 mm. height 8.4 mm. not including the aneroid drum.
Movement: diameter 23.1 mm., height 8.4 mm.
Provenance: Purchased in 1989 with the aid of funds from the Dingwall Bequest.
(1) A difference of 10 mm of mercury represents 125 metres difference in height. The ring is set to ones known altitude at the commencement of the climb one is undertaking. The altitude is then read from the position of the red hand. Unfortunately this will not allow for the changes in the ambient pressure. To do this one would have to listen to a radio for updates - weather reports will give the pressure at sea level. This will not normally vary from day to day very much but under exceptional circumstances could be as much as 100 mm which could compromise ones altitude reading by 1250 metres!
(2) The firm founded in 1923 by Charles Berner and affiliated to the Ebauche Group in 1933. The company is in Peseux, Neuchâtel.
- Not on display
- Acquisition date
- Britain, Europe and Prehistory
- Registration number